Linear light emitting devices are known in the art. US-2008/0002421 for instance describes a linear light emitting apparatus including a light source a linear light guide member into which the light of the light source is guided from one end side thereof, and also which includes a projecting portion extending continuously along the longitudinal axis of the linear light guide member. In the upper surface of the projecting portion, there are formed light expanding and reflecting portions each extending over the entire width of the upper surface at given intervals.
This document further describes that on the upper surface of the projecting portion, there are formed light expanding and reflecting portions. The light expanding and reflecting portions can be formed by applying or printing an expanding and reflecting paint, or by enforcing a light expansion and reflection processing such as a drawing operation, or by bonding a light expansion and reflection tape. When the light expanding and reflecting portion is formed by printing, there can be used an acrylic system paint, an epoxy system paint, a urethane system paint or the like. Each light expanding and reflecting portion is formed such that it extends over the entire width of the upper surface of the projecting portion. That is, each light expanding and reflecting portion is formed in such a manner that it extends continuously from one of the two sides of the upper surface of the projecting portion to the other both of which are parallel to the longitudinal axis of the projecting portion. The light expanding and reflecting portions are formed at given intervals in the longitudinal axis direction of the projection portion. For example, the light expanding and reflecting portions are respectively formed such that the more distant the light expanding and reflecting portions are, the higher the densities thereof are.